How to remove Apple TV restriction passcode from Netflix?

It’s not actually a Netflix passcode you’re running into — it’s the Apple TV Restrictions (Parental Controls) passcode being applied to all third-party apps, including Netflix. When Restrictions are turned on, Apple TV treats certain apps as restricted content sources, so it will always ask for the same 4-digit Restrictions passcode before launching them.

To stop Netflix from asking for the passcode, you need to adjust the Apple TV Restrictions settings, not anything inside Netflix.

Try this:

1. Go to Settings → General → Restrictions.
2. Enter your Restrictions passcode.
3. Under the Restrictions options, look for Allowed Content or Apps.
4. Change the setting so that third-party apps are allowed without requiring the passcode.
5. On some Apple TV models, you can set Apps: Allow All or choose an age rating that includes Netflix.
6. Exit the menu — Netflix should now open without asking for the passcode.

Important:

• If you turn Restrictions off entirely, it removes the passcode everywhere — but as you said, that also removes all parental controls.
• Adjusting the Apps or Allowed Content section lets you keep restrictions on Apple TV itself while still letting your son access Netflix without entering a code.
• If you don’t see those options, let me know which Apple TV model and tvOS version you have and I can walk you through the exact path...

Restrictions apply to a group of apps based on age, not specific apps. There is no granular control for that.

If you want to stop Netflix from requiring a passcode, then you need to adjust restrictions for apps so Netflix is not included any more. This of course will also release other apps in the same age group.

The restriction is set in Settings ➡️ General ➡️ Restrictions ➡️ Allowed Content ➡️ Apps